1. Field of the Invention
The present invention relates to a power supplying device, and in particular to a power supplying device with low standby power consumption.
2. Description of Related Art
Reference is made to FIG. 1, which is a circuit block diagram of a conventional power supplying device. The power supplying device 1 is connected to an alternative current (AC) power supplier ACP and an electronic system PS. The power supplying device 1 receives an AC electric power provided by the AC power supplier ACP and then outputs a converted electric power with power conversion to the electronic system PS. The power supplying system 1 is provided to be operated in a normal mode or a standby mode. In the normal mode operation, the power supplying device 1 provides an electric power to operating electronic system PS, namely, the electronic system PS is operated in turn-on mode. On the contrary, in the standby mode, the electronic system PS is operated in turn-off mode.
The power supplying device 1 includes an electromagnetic interference filter 10, a rectifier 11, a main power converter 12, an auxiliary power converter 13, a first controller 14, a second controller 15, a power manager 16, a first optical isolator OC1, a second optical isolator OC2, a third optical isolator OC3, and a forth optical isolator OC4.
The electromagnetic interference filter 10 is electrically connected to the rectifier 11. The rectifier 11 is electrically connected to the main power converter 12 and the auxiliary power converter 12. The first controller 14 is electrically connected to the rectifier 11 and the main power converter 12. The second controller 15 is electrically connected to the auxiliary power converter 13. The power manager 16 is electrically connected to the main power converter 12 and the auxiliary power converter 13.
The first optical isolator OC1 is electrically connected to a first electric power outputting terminal VA of the main power converter 12 and the first controller 14. The second optical isolator OC2 is electrically connected to a standby electric power outputting terminal Vsb of the auxiliary power converter 13 and the second controller 15. The third optical isolator OC3 and the forth optical isolator OC4 are electrically connected to the power manager 16 and the first controller 14, respectively. The first optical isolator OC1, the second optical isolator OC2, the third optical isolator OC3, and the forth optical isolator OC4 are respectively an optical coupler.
The power supplying device 1 receives AC electric power outputted by the AC power supplier ACP. The electromagnetic interference filter 10 receives the AC power source outputted from the AC power supplier ACP and filters electromagnetic interference of the AC power source. The rectifier 11 is used for converting the AC electric power outputted form the electromagnetic interference filter 10 into a direct current (DC) electric power. The rectifier 11 includes a power factor correction circuit 110 for decrease inputting current.
The main power converter 12 receives the DC electric power outputted form the rectifier 11 and is controlled by the controller for modulating the levels of the electric powers outputted form the first electric power outputting terminal VA and the second electric power outputting terminal VB. The main power converter 12 is a DC to DC power converter such as an LLC resonant power converter, a dual forward power converter or a single forward power converter. The auxiliary power converter 13 receives the DC electric power outputted form the rectifier 11 and is controlled by the second controller 15 for modulating the level of outputting electric power. The auxiliary power converter 13 is, for example, a flyback power converter.
The main power converter 12 outputs electric powers with power conversion from the first electric power outputting terminal VA and the second electric power outputting terminal VB when in the normal operation, however in the standby operation, the main power converter 12 has no power conversion and does not output electric powers (namely the first electric power outputting terminal VA and the second electric power outputting terminal VB do not output electric powers). The auxiliary power converter 13 not only outputs electric power with power conversion from the standby electric power outputting terminal Vsb in the normal operation, but in the standby operation. In standby operation, the power supplying device 1 stops the main power converter 12 outputting electric power, which can effectively reduce power consumption in standby operation and achieve power reservation.
However, the volume of the power supplying device 1 simultaneously including the main power converter 12 and the auxiliary power converter 13 is large, and in normal operation, the main power converter 12 and the auxiliary converter 13 are respectively proceeded power conversion, and the power consumption of the power supplying device 1 in normal operation is then increased.